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A mix of easy, medium and hard — questions run from warm-up to expert, so there's a real challenge at every level. Think you know the answers? Play to find out.
The tallest mountain in the world, standing at 29,032 feet, sits on the border between Nepal and this region.
Difficulty: EasyThis European capital is actually two cities united in 1873, separated by the Danube and connected by the iconic Chain Bridge.
Difficulty: MediumThis dark metamorphic rock visible at the bottom of Grand Canyon is part of the basement complex and dates back 1.7-1.8 billion years.
Difficulty: HardThis massive canyon in Arizona was carved by the Colorado River over millions of years.
Difficulty: EasyThis is the only continent that spans all four hemispheres of Earth.
Difficulty: MediumThis low-lying island nation in the Indian Ocean, with an average elevation of just 4 feet, is the world's lowest country and at severe risk from rising sea levels.
Difficulty: MediumThis autonomous monastic community on a Greek peninsula has barred women and female animals for over 1,000 years and is home to 20 Eastern Orthodox monasteries.
Difficulty: HardThis Arizona park is home to one of the world's most spectacular gorges, carved by the Colorado River over millions of years.
Difficulty: Easy